Generally, elevators provide a method of transportation for moving persons or objects between floors of a building. These elevators include cars which travel within an elevator shaft. The cars are connected to a counterweight by hoist cables, all of which are oriented vertically within the shaft. Movement to a desired floor is achieved by electrically powered motors. These motors rely upon the building's power source and are controlled by electrical systems within the building.
During an emergency situation, such as an earthquake, fire or terrorist attack, the power within the building is often disrupted. Therefore, the conventional elevator system becomes unreliable. As a result, travel between floors during the emergency is reduced to the use of stairs, ladders or articulated arms. If the floor involved is relatively high (e.g. 50-100 floors), or if there are floors above a fire, ladders and articulated arms may not be able to reach the desired floor from the exterior of the building. Accordingly, the stairs may be used for persons to evacuate the building. However, considering that the evacuating persons will start from a relatively high floor, it will be hard-pressed and time consuming for the persons to walk down the stairs to safety.
Moreover, in the absence of conventional elevator service, emergency workers such as firefighters must hand carry any firefighting equipment to the affected area. This drastically reduces the amount of equipment than can be carried and the speed with which it can be deployed.
Therefore, there is a need for an elevator system which provides a reliable independent means to transport persons and objects between floors of a building during an emergency.